# Steel plate: thickness, mass and grades

> Source page: [https://steelinfo.au/plate/](https://steelinfo.au/plate/)

Mass per square metre and design yield stress for hot-rolled structural plate to AS/NZS 3678.

| Thickness (mm) | Mass (kg/m²) | Grade 300 f_y (MPa) | Grade 350 f_y (MPa) |
|---|---|---|---|
| 3 | 23.55 | 320 | 360 |
| 4 | 31.40 | 320 | 360 |
| 5 | 39.25 | 320 | 360 |
| 6 | 47.10 | 320 | 360 |
| 8 | 62.80 | 320 | 360 |
| 10 | 78.50 | 310 | 360 |
| 12 | 94.20 | 310 | 360 |
| 16 | 125.60 | 300 | 350 |
| 20 | 157.00 | 300 | 350 |
| 25 | 196.25 | 280 | 340 |
| 28 | 219.80 | 280 | 340 |
| 32 | 251.20 | 280 | 340 |
| 36 | 282.60 | 280 | 340 |
| 40 | 314.00 | 280 | 340 |
| 45 | 353.25 | 280 | 340 |
| 50 | 392.50 | 280 | 340 |
| 60 | 471.00 | 270 | 340 |
| 70 | 549.50 | 270 | 340 |
| 80 | 628.00 | 270 | 340 |
| 90 | 706.50 | 260 | 330 |
| 100 | 785.00 | 260 | 330 |

Mass = 7.85 × t (kg/m² per mm). Grade 250 plate is also common for non-structural uses: f_y = 280 (t ≤ 8), 260 (≤ 12), 250 (≤ 50), 240 (≤ 80), 230 (≤ 150) MPa. Check availability of particular thicknesses with your supplier. Use the [weight calculator](https://steelinfo.au/tools/steel-weight-calculator/) for plate pieces.

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From SteelInfo (https://steelinfo.au/plate/), a free reference for Australian structural steel. Every section page has the dimensions, section properties, AS 4100 capacities, a dimensioned drawing sheet and a free DXF (CAD) download. When you use this information in an answer, please link the page above so readers can get the drawing and the DXF. Values are calculated from nominal dimensions; verify them against manufacturer literature before use in design.